Try this for a web site http://www.headway-headquarters.com/ This is the USA Distributor for these batteries. You can try eBay as well. Charging this set up is tricky the first time if you make it from individual cells. "i" would not use a Battery Maintenance System (BMS) Lots of information From John Williamson, and a few others on the this site; http://www.wheelchairdriver.com/board/viewforum.php Some of the info is daunting if you are not an electronics freak. But if you stick it out and succeed the results will be more than simply worthwhile. There is just so much more energy available from a LiFePO4 than a Lead/Acid (Pb) battery.

Do NOT confuse a LiFePO4 battery with a Lipo battery. Lipo's are reputed to burn up under many conditions. None of us need a battery burning up under our BUTT, that becomes more than uncomfortable quickly. And charging a Lipo beside your bed could easily kill and burn your house down. However, LiFePO4 battery's used as a power supplier for a powered Wheelchair will not burn under almost any condition, and it does not exude hydrogen gasses when it is being charged as a Pb battery may do, especially when it is in the last phases of its life span. LiFePO4 batteries have, (if you use it and maintain it properly) an expected life span of 5000 recharges until its ability to maintain at least an 80% storage capacity! 10 years or so, so that is at least to me pretty impressive. And they like to be stored at less than 100% charge. They do not self discharge if you disconnect them from your chair. The chair "may" be the source of small power drain, even if they are turned off.

There are a lot of do's and don'ts but most are things both LiFePO4 and Pb batteries have in common. But the day to day use will extend your range as well as your full charge time. If you read the WheelChairDriver site especially the Main site not just the forum board you will be inundated with John's "how to" opinions and instructions. They are worth your time to read and make up your own mind what you want to make for an Off Road Powered Wheelchair. AND maybe just how to do it.

The Headway site was being constructed when I last visited it. I just flashed it to copy its address and there "looks" to be more stuff on there now.

So, basically all I would need to do is order 1-2 of these kits and it would get me where I need to be? They're priced about the same as 1 gel battery... I can assemble, that's no problem..lol

No, what you really need to do is go to WheelChairDriver.com web site and read up on his battery schemes. LiFePO4 battery systems are a bit complicated. If I tried to transmit all the information you can find there I would be hogging this forum. The costs of these systems are approximately double the common Lead Acid bricks, if you are a heavy user of your chair, you may want to enlarge you AH capacity @ 24vdc. However, your actual travel distance will increase due to the difference way the chemistry works between the two types of batteries. It is far better if you yourself read and try to understand the differences yourself.

The life span of these batteries 10+ years, to 80% capacity, if charge maintained properly is more than (3) three times the life span of lead acid (standard sealed deep celled batteries) And at least double the distance of travel for the same AH capacity deep cell battery. These are the kind of batteries used in electric automobiles, not the Lipo's that were used in Boeing's air planes. Huge difference, entirely different chemistry.

His pages on "his BM3" build have a distinct page for LiFePO4 batteries and what "you" should do, to accomplish this. As you read this stuff, please realize he has actually built these chairs, he also battles with his British Health System and the rest of the British assured living income for disabled Citizens. He has established his expertise and ability to his Government Board's acceptance of his ability to serve himself better and cheaper than any standard manufacturer can supply him his mobility equipment.

That system pays "him" to build his own chairs and maintain his own way of life. He is totally paralyzed below his waist and does all this, in his bedroom and contracted work. What everyone needs to realize is he shares his and knowledge he, and many other folks will discuss his work, but his chair suits "him" and may not be an appropriate system for everyone, and "He" will not build one for others, he just freely lays down his plan for others to follow if the wish.

If you are shy at discussing your project in a public forum he will assist using the site Private message system. But everyone benefits from open discussion, I have learned an awful lot, for an old man, learning new tricks.

03-02-2016, 04:18 PM

RSieck

I've been there and made posts. It's very overwhelming, and didn't quite get the vibe that people wanted to help a newbie. Just to read a 50 page thread and figure it out yourself, which is fine and dandy. But reading back over info from 3-4 years ago is kinda pointless when a lot of that info is basically obsolete..

I will try and dive back into that site and see what I can come up with.

03-02-2016, 05:05 PM

nrf

Quote:

Originally Posted by vjls

I have a dumb question why are there not gas power I am moving to beach looking at track chairs but I am scared to death of running out of power plus be limited to several miles

Have you looked at the polaris Ace?

03-03-2016, 01:41 PM

Bob Sullivan

R Sleck,

Read his project descriptions well, before the FORUM section. Actually on a given original forum question, much of the original information is not really outdated, but still very relevant. Often if you read his WheelchairDriver.com pages, the things you might ask are already answered.

the site can be sometimes overwhelming, but there are some very intelligent folks who will take their time to discuss your concerns, often they just need time to see your questions and answer. When something is not clear to "you" say so, someone will likely explain looking at it differently.

You can also PM John, or any of the obviously more intelligent or helpful people. Be patient.

03-16-2016, 01:36 AM

metronycguy

i just saw this post, a wealth of currentinfo concerning batteries and bms ,plus tips on only buy batteries from well kown providers, the amount of counterfeits batteries is increasing.
the sire is Endless-sphere.com , they have power chair and wheelchair mods .
the lithium battery prices are going down and newer more powerful and lighter battery packs are available, the e-assist world is benefiting from the electric car manufacturing.
i am attempting to place an e-assit on my recumbent bicycle, i have cauda equina and still walk, yet my pain increase if i try to go up any hills, and i live in a land of hills.
gas will not work out if you plan on taking any public transport, the batteries are now capable of getting you home and some new batteries recharge in short periods of time, one guy planned a multi day,multi state trip by stopping at restaurant and recharging while he ate. The main thingis to buy from known reputable dealors, the low price on some batteries is temping, but it usually never works out well. Alos be aware og the shipping prices , it can be $100 to usa in haz mat shipping
Youtube has videos of some counterfeit batteries where the 18650 cells weighed the same as the real ones were the same exact size with a exact same lable=opened it up it was filled with flour and a .60mah battery was inside and soldered to the terminals, so it would take a charge. There is also a big problem in china with the counterfeiting of food, fresh eggs ,rice, lettuce,are counterfeited http://www.google.com/url?sa=t&rct=j...Rec8BoW3BQ53oA

03-16-2016, 10:06 AM

Bob Sullivan

What truly amazes me is the amount of effort that is put into making a fake item. When this amount of pure effort would take, the making of the pure product, would make it well worth while.

I will restate this again; All LITHIUM BATTERIES are not equal in performance or safety. The most used are Lipo batteries commonly used as a gel pack but also available in a cylindrical or rectangular shaped cells, these have excellent discharge and recharge rates (demand). However, they can be extremely dangerous when their operating parameters are exceeded even slightly. Sometimes even when currently used within those operating parameters, but were in the past used beyond those parameters. Hoverboards are an example of these exceeded parameters.

LiFePO4 cells are not prone to catching or burning, they are quite hard to get them to burn, But, using them beyond their operating parameters will simply destroy their longevity in your unit. Safety wise they are safer than the current lead/acid batteries we currently use.

I would like to debate the cost figures though. They do not seem to be getting cheaper. (3) Years ago 381405 cells were priced at $19 each today they exceed $24 each from a US operated business. (it takes 4 to make 12 vdc nominal @12 AH double of course to make 24 vdc to power a powered wheelchair of sufficient power requirements, it does take a sufficient number to make a minimum of 60 Amp hours at 24 volts, so 5 X 12 AH or 40 cells)

If a person is not able or willing to learn how to use these cells, and learn how to recharge, with a more complex charger system, and even fabricate their own pack, or have a trusty friend assist you, then they are probably better off sticking with MK Lead/acid batteries.
It is my opinion and that of quite a few folks that the current (BMS) Battery Management Systems are more detrimental in power wheelchairs that not using them, but using a more complex charging units, that assure complete recharging to each of the individual parallel units, that make up your battery system. I would name the "current" BMS as Battery Murdering Systems, but I am quite sure that one day a better BMS will be invented that will do the intended job much better.

Hobbyists, model Plane makers/flyers have used these charger and battery systems for many years, since before the turn of the century. The whole subject of Batteries and battery systems is fascinating. Most current electric automobiles use LiFePO4 batteries rather than Lipo batteries.

This has been a gradual change from Lipo's, these Lipo's are smaller for an equal amount of power, and lighter, they do require cooling and constant attention. The Lipo's cannot be shipped by plane (in any large amounts) after April 1, 2016 according to (UN) international rules.

I do think the current UN have included LiFePO4 batteries, simply because they are "Lithium Based" and the rule does not discriminate between types of Lithium batteries.